Simulation of Gas Diffusion In Polymer Nanocomposites

ABSTRACT:  The effects of nanoparticles on the rates of gas diffusion through glassy polymers were studied by a combination of molecular dynamics and Monte Carlo techniques.  These techniques were used to overcome the large amount of computational time required to obtain gas trajectories in the diffusive regime for glassy systems.  Polystyrene was simulated using molecular dynamics with a number of gas molecules to obtain a probability profile of gas motion within the polymer matrix at a range of temperatures above and below glass transition temperature.  These results were used in conjunction with MD simulations to examine the types of gas particle motion as a function of these temperatures.  The use of the a time extending kinetic Monte Carlo allowed simulation of a sufficient time frame to calculate gas motion in the diffusive regime.  We studied the effect of Fullerene nanoparticles added to the polymer upon the gas diffusivity in such polymers.  These results will be discussed in this talk along with a mechanistic explanation of our observations.